Wednesday, May 23, 2012By George Jahn ,AP

VIENNA -- Despite some remaining differences, a deal has been reached with Iran that will allow the U.N. nuclear agency to restart a long-stalled probe into suspicions that Tehran has secretly worked on developing nuclear arms, the U.N. nuclear chief said Tuesday.

The news from International Atomic Energy Agency (IAEA) chief Yukiya Amano, who returned from Tehran on Tuesday, comes just a day before Iran and six world powers meet in Baghdad for negotiations and could present a significant turning point in the heated dispute over Iran's nuclear intentions. The six nations hope the talks will result in an agreement by the Islamic Republic to stop enriching uranium to a higher level that could be turned quickly into the fissile core of nuclear arms.

Iran denies it seeks nuclear arms and says its reactors are only for power and medical applications.

By compromising on the IAEA probe, Iranian negotiators in Baghdad could argue that the onus was now on the other side to show some flexibility and temper its demands. Although Amano's trip and the talks in Baghdad are formally separate, Iran hopes progress with the IAEA can boost its chances Wednesday in pressing the U.S. and Europe to roll back sanctions that have hit Iran's critical oil exports and blacklisted the country from international banking networks.

It was unclear, though, how far the results achieved by Amano would serve that purpose, with him returning without the two sides signing the deal, despite his upbeat comments.

After talks in Tehran between Amano and chief Iranian nuclear negotiator Saeed Jalili, “the decision was made ... to reach agreement” on the mechanics of giving the IAEA access to sites, scientists and documents it seeks to restart its probe,” Amano told reporters at Vienna airport after his one-day trip to Tehran.

Amano said differences existed on “some details,” without elaborating but added that Jalili had assured him that these “will not be an obstacle to reach agreement.” He spoke of “an almost clean text” that will be signed soon, although he could not say when.

Western diplomats are skeptical of Iran's willingness to open past and present activities to full perusal, believing it would only reveal what they suspect and Tehran denies — that the Islamic Republic has researched and developed components of a nuclear weapons program. They say that Tehran's readiness to honor any agreement it has signed is the true test of its willingness to cooperate

The United States is among those skeptics. In a statement released soon after Amano's announcement, Robert A. Wood, America's chief delegate to the nuclear agency, said Washington appreciated Amano's efforts but remained “concerned by the urgent obligation for Iran to take concrete steps to cooperate fully with the verification efforts of the IAEA, based on IAEA verification practices.”

“We urge Iran to take this opportunity to resolve all outstanding concerns about the nature of its nuclear program,” said the statement. “Full and transparent cooperation with the IAEA is the first logical step.”

For the six powers — the United States, Russia, China, Britain, France and Germany — a main concern is Iran's production of uranium enriched to 20 percent, which is far higher than needed for regular energy-producing reactors but used for one Iran says it needs for medical research. The U.S. and its allies fear the higher-enriched uranium could be quickly boosted to warhead-grade material.

U.S. officials have said Washington will not backpedal from its stance that Iran must fully halt uranium enrichment. But speculation is increasing that the priorities have shifted to block the 20-percent enrichment and perhaps allow Iran to maintain lower-level nuclear fuel production — at least for now.

Iranian officials could package such a scenario as a victory for their domestic audience. In Israel, it would likely be greeted with dismay and widen rifts between President Barack Obama's U.S. administration and Israeli officials who keep open the threat of military action against Iran's nuclear sites.

Israeli Prime Minister Benjamin Netanyahu has warned against concessions, saying world powers should make “clear and unequivocal demands” that Iran stop all of its nuclear enrichment activity.

“Iran wants to destroy Israel and it is developing nuclear weapons to fulfill that goal,” Netanyahu said at a conference in Jerusalem. “Against this malicious intention, leading world powers need to display determination and not weakness. They should not make any concessions to Iran.”